After its first week out on the market, Colin McRae: DiRT by Codemasters has hit the half-million mark in global sales. The game's demo has been downloaded more than 500,000 times and the actual sales figures are just a shade behind.

Codemasters CEO Rod Cousens comments "This success with DiRT is a text-book case of our product development, marketing and distribution efforts all working together to ignite consumer interest and drive sales."

Cousens also revealed that almost half of the game's first-week sales were from the United States, and said that the distribution is a sign that the DiRT franchise is catching on internationally.

DiRT is available now for the Microsoft Xbox 360 and the PC. A Sony PlayStation 3 version will be released later this year and is also expected to sell well in the platform.